Facile Synthesis of Polyaniline@UiO-66 Nanohybrids for Efficient and Rapid Adsorption of Methyl Orange from Aqueous Media

Abstract

A series of UiO-66/polyaniline (UiO-66/PANI) nanohybrids with various UiO-66 to aniline weight ratios ranging from 0.01 to 0.1 was synthesized using an in situ polymerization technique. The adsorption behavior of the neat PANI nanofiber network and the synthesized nanohybrids was examined toward anionic methyl orange (MO) dye from aqueous media. It was realized that the maximum adsorption capacity of PANI (229 mg/g) increases steadily by increasing the UiO-66 content in the nanohybrid up to 7 wt % at 426 mg/g, and then, it approximately levels off at 432 mg/g for the nanohybrid sample containing 10 wt % UiO-66, that is, UP10. Based on a thorough characterization, it was shown that UiO-66 is completely encapsulated by PANI nanofibers. Further adsorption examinations on the nanohybrids exhibited that the Langmuir isotherm model and pseudo-second-order kinetics model best describe the adsorption performance of all the prepared adsorbents during the adsorption of MO. Meanwhile, thermodynamic investigations demonstrated that the adsorption of MO onto UP10 is endothermic and spontaneous, and entropy controls the adsorption process. UP10 exhibited high selectivity indices of 100, 20, and 34 for the adsorption of MO as an anionic dye over crystal violet (CV), malachite green (MG), and methylene blue (MB), respectively, as cationic dyes.

Adsorption Behavior of a Gd-Based Metal–Organic Framework toward the Quercetin Drug: Effect of the Activation Condition

“…Metal–organic frameworks (MOFs) are hybrid inorganic–organic porous materials. The inorganic part includes metal ions (clusters), and the organic part consists of bridging linkers between the metal ions. − In recent years, MOFs have attracted the attention of researchers, especially those working in the biotechnology field including drug delivery, drug adsorption, image contrast agents (CAs), and tissue engineering. − The popularity of MOFs is due to their crystalline structure, porosity, high surface area, ease of functionalization, and tunable size. − Among various MOFs, lanthanide-containing MOFs are intriguing in the bioimaging field. The metal in this class of MOFs shows photoluminescence and magnetic properties, which can play the role of a CA in imaging and as a result make lanthanide MOFs promising multifunctional materials for treatments, biosensors, and imaging. − …”

Development of pH-Sensitive UiO-66/Polyaniline Nanohybrids with Self-Healing Anticorrosive Performance in Epoxy Coatings

“…As deduced from Figure 2b, the XRD pattern of nanohybrids at low UiO-66 content, i.e., H5, lacks many crystalline peaks of UiO-66, suggesting that UiO-66 is buried inside the PANI, as reported in our earlier work. 42 However, by increasing the amount of UiO-66 in the nanohybrids, the characteristic peaks of UiO-66 get appeared, particularly beyond 2θ = 25°for H50. Moreover, the crystalline sharp peak of UiO-66 at 7.45 and 8.65°becomes more evident by increasing the content of UiO-66 in the nanohybrids.…”

Metal–Organic Framework-Based Aerogel: A Novel Adsorbent for the Efficient Removal of Heavy Metal Ions and Selective Removal of a Cationic Dye from Aqueous Solution

“…These triphenylmethane dyes may be tumorigenic and mutagenic . Probably all commercial brands of CV are in vitro potent carcinogen, mitotic poison and show seviour cytogenic toxicity. , Therefore, the introduction of innovative, affordable, and energy-efficient protocols for removing trace pollutants from water cannot be overemphasized …”